One-piece sleeve and nut coupling means

ABSTRACT

A coupling for use in coupling a tube. The coupling means includes a one-piece sleeve and nut element connected by a frangible connector with the sleeve being constructed to permit turning under of the connector upon shearing thereof in the makeup of the fitting. By thusly accommodating the connector within the sleeve, the connector is prevented from wedging between the tube and nut and thereby permits ready disassembly of the coupling when desired.

i United States Patent 1 1 1 3,743,324 Schwarz et al. July 3, 1973ONE-PIECE SLEEVE AND NUT COUPLING 3.290.062 12/1966 Ziherl et al. 285/3MEANS I FOREIGN PATENTS OR APPLICATIONS Inventors: Albert J- Schwarz,Lincolnwood, 925,028 3/1955 Germany 285/3 Richard A. Misak, Ch1cago,both of 646,788 1 l/ 1950 Great Britain 285/3 Ill. PrimaryExaminer-Thomas F. Callaghan [73] Ass1gnee. Imperial Eastman CorporatmnAtmmey nofgrem wegner Allen, stcnma & [22] Filed: Mar. 15, 1972 McCord[21 Appl. No.: 234,808

[57] ABSTRACT 52 us. c1 285/3, 285/343, 285/3827 A P for use "P""8 atube The Cowling 51 1111. C1 F16! 19/08 means includes -P sleeve ande'emem [58] Field of Search 285/3, 4, 2, 382.7, connected by a frangibleconnector with Slave 285/341, 342, 343, 3345 being constructed to permitturning under of the con- 1 nector upon shearing thereof in the makeupof the fit- References Cited ting. By thusly accommodating the connectorwithin the sleeve, the connector is prevented from wedging UNITED STATESPATENTS between the tube and nut and thereby permits ready RMCLIIOdShdisassembly of the Coupling h desired. |c ar son 2,544,109 3/ 1951Richardson 285/3 13 Claims, 5 Drawing Figures 2,641,489 6/1953 Hedberg285/3345 X BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates to tube couplings and in particular to tube couplingsutilizing sleeve and nut means for urging the sleeve into sealedengagement with the tube.

2. Description of the Prior Art 7 In one prior art tube coupling, aone-piece nut and sleeve element is provided for cooperation with a bodyelement permitting the sleeve to shear off from the nut and becomeattached to the tube in the make-up of the fitting. By integrallyconnecting the sleeve to the nut, alignment of the sleeve with the bodymember is automatically effected. Further, such one-piece constructionassures the use of the sleeve and effectively precludes installation ofthe sleeve backwardly in the fitting. An excellent example of such aone-piece nut and sleeve tube coupling is that manufactured by theassignee hereof and identified as a Hi'Duty fitting. The Hi-Duty fittinghas been found to provide facilitated installation and manufacturingeconomy as a result of the one-piece sleeve and nut construction. Thefitting is adapted for use with a customers port machined into thecustomers device, such as a valve pump, etc. Thus, the conventionalfitting body may be eliminated.

Further, it has been found, that as the sleeve is an integral part ofthe nut on initiation of the make-up of the fitting, the sleeve isguided by the nut and prevented from cocking until the deflectible noseportion thereof has been deflected substantially into contact with thetube. As the sleeve effectively contacts the tube at the time thefrangible connector breaks, the sleeve is effectively prevented fromcocking in the make-up of the joint.

In assignees prior construction, the connector between the sleeve andnut was provided by a pair of axially spaced grooves, one groove openingradially inwardly and the other opening radially outwardly so as todefine an axially thin radial wall which broke in the making up of thefitting to provide the desired separation of the one-piece assembly intodiscrete sleeve and nut elements. Thus, in the prior design, the nutbecame a separate element intended to permit disassembly of the fittingwhen desired, while leaving the sleeve permanently sealingly secured tothe tube.

However, it was found that the somewhat expensive procedure of machininga radially inwardly opening groove in the mid-portion of the assemblycould be dispensed with by providing a single outwardly opening grooveleaving a thin radially inner axially extending connecting wall betweenthe sleeve and nut. This design was utilized in connection particularlywith the smaller fittings where utilizing a recessed tool in therelatively small diameter bore was quite difficult. However, it wasfound that the manufacture of the fitting with the thin axiallyextending wall presented manufacturing problems. Thus, it was found thatthe radial motion of the cutting tool placed a transverse load on thefitting which, at times, tended to break off the sleeve from the nutwhile the fitting was being machined. One attempted solution to thisproblem was to increase the wall thickness of the connector portion, butit was found that the wall thickness must be maintained quite small topermit proper shearing of the wall as a result of the normal make-upforces generated. Further, it was found that there was a tendency forthe broken connector to turn inwardly so that the portion remainingconnected to the sleeve at time wedged itself between the nut and tubeand,thus, effectively locked the nut and sleeve together on the tube,making it extremely difficult to withdraw the nut in disassembling thefitting.

SUMMARY OF THE INVENTION The present invention comprehends an improvedtube coupling utilizing an improved, one-piece sleeve and nut assemblywherein the connector is formed by providing a radially outwardlyopening groove between the sleeve and nut portions and providing acylindrical recess through the sleeve and connector portion up to thenut. The cylindrical recess provides two improved functionings in thepresent fitting effectively assuring ready removability of the nut whendesired after the coupling is fully made up.

More specifically, the broken connector wall is caused to turn underfrom the sleeve so that the distal portion thereof is received in theannular recess within the sleeve. Thus, the broken connector iseffectively directed away from the nut and prevented from wedgingbetween the nut and tube. The recess is preferably maintained as smallin radial dimension as practical while permitting reception of theconnector end therein so as to permit minimum deflection of the noseportion of the sleeve to effect the desired sealed connection to thetube.

Secondly, the provision of the recess may be effected as the lastmachining operation, permitting the wall of the connector as firstdefined by the radially outwardly opening groove, to be relatively thickso as to avoid breaking of the connector portion during the machining ofthe groove. The machining of the recess comprises an axial machiningoperating which minimizes any tendency for breaking of the wall so thatthe final thin wall may be readily provided by a relatively low cost,high speed machining operation.

In the illustrated embodiment, the recess has a depth of approximately0.002 to 0.003 inch with the connector wall having a radial dimension ofapproximately 0.003 inch.

Thus, more specifically, the invention comprehends the provision of aone-piece coupling element for coupling a tube to a female couplingelement having a port defining an axially inner camming surface andincludes a tubular member having an axial bore adapted to coaxiallyreceive the tube to be coupled, an axially inner sleeve portion having atapered outer surface adapted to engage the camming surface of thefemale coupling element and be deflected radially inwardly thereby intosealed, locked association with the tube as the result of an axiallyinward movement of the inner portion thereagainst, an axially outerthreaded nut portion adapted to threadedly engage the thread of thefemale coupling element for effecting axial movement of the malecoupling element relative to the female coupling element as an incidentof rotation of the male coupling element relative to the female couplingelement, a frangible mid-portion connecting the sleeve portion and nutportion, adapted to be broken adjacent the nut portion in the make-up ofthe coupling, the mid-portion being defined by a radially outwardlyopening annular groove, and an annular recess extending coaxially aboutthe bore from the axially inner end thereof to radially inwardlyadjacent the mid-portion groove, the frangible portion defining aradially thin connection extending axially between the sleeve portionand nut portion and radially between the radially outwardly openingannular groove and the annular recess and having an inner diametersubstantially greater than the diameter of the mid-portion whereby thebroken frangible portion is caused to turn under from the sleeve portionand extend into the recess radially within the sleeve portion andthereby be prevented from projecting to between the tube and the nutportion in the made-up arrangement of the coupling.

The present invention is extremely simple and economical of constructionwhile yet providing the highly desirable features discussed above.

BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of theinvention will be apparent from the following description taken inconnection with the accompanying drawing wherein:

FIG. 1 is a side elevation of a coupling embodying the invention havinga tube end connected thereto;

FIG. 2 is a side elevation thereof prior to make-up of the coupling;

FIG. 3 is an enlarged fragmentary diametric section thereof as uponinitiation of the make-up of the cou- P g;

FIG. 4 is a diametric section similar to that of FIG. 3, but uponcompletion of the make-up of the coupling; and

FIG. 5 is a side elevation of the tube with the nut withdrawn axiallyfrom the sleeve as in disassembly of the coupling.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the exemplary embodiment ofthe invention as disclosed in the drawing, a tube coupling generallydesignated is shown to comprise a one-piece sleeve and nut assembly 11including an axially inner sleeve portion 12, an axially outer nutportion 13, and a connector portion 14 extending between the sleeve andnut portions. The one-piece assembly 11 is adapted for connecting a tubeT to a female coupling element, such as the coupling element 15,defining a portion 16 having an axially inner camming surface 17 and anaxially outer female threaded portion 18. The nut includes a threadedouter portion 19 adapted to threadedly engage threaded portion 18 ofelement to axially advance the sleeve 12 against the camming surface 17to urge a deflectible nose portion 20 of the sleeve radially inwardlyinto sealed locked engagement with the tube, as shown in FIG. 4.Threading torque may be applied to the nut by means of a suitable tool,such as wrench (not shown), applied to suitable tool engaging flats 21on an outer end portion 22 of the nut.

The assembly 11 defines an axial bore 23 in nut portion 13 which snuglyreceives the tube T. The sleeve 12 and connector 14 define acontinuation of bore 23 effectively enlarged by an annular recess 24opening axially inwardly through the deflectible portion 20 of thesleeve and extending axially outwardly to a radial planar end surface 25at the inner end of the nut. Thus, as seen in FIG. 3, the recess 24provides a clearance space between the outer surface of the tube T andthe inner surface of the sleeve 12.

The frangible connector 14 defines a mid-portion of the assembly 10integrally connecting the sleeve and nut portions and adapted to bebroken in the make-up of the coupling adjacent the nut end surface 25 asa result of the torque generated between the nut and the sleeve as thesleeve contacts the tube T when nose portion 20 is deflected thereinto.The frangible midportion 14 is defined by a radially outwardly openingannular groove 26 and the outer end of the recess 24, as best seen inFIG. 3, to comprise a thin-walled tubular connector spaced radiallyoutwardly of the tube T. The bottom sufface of the groove 25 maycomprise a right cylindrical surface 27 and the side walls of the groove26 may comprise radial planar surfaces 28. The axially outer side wallof the groove is substantially congruent to the outer end of the recess24 defined by the end wall 25 of the nut.

The radial thickness of the connector wall 14 is preferably very smallso as to permit facilitated shearing thereof while yet effectivelymaintaining the one-piece assembly prior to make-up of the coupling.Illustratively, where the tube T has an outer diameter of approximatelyone-fourth inch or smaller, the connector wall 14 may have a thicknessof approximately 0.003 inch. The radial depth of the recess 24 iscoordinated with the thickness of the connector portion to assurereception of the turned end thereof into the recess 24 in making up thecoupling, as shown in FIG. 4. It has been found that a recess depth ofapproximately 0.002 to 0.003 inch similar to the thickness of theconnector wall provides excellent functioning of the coupling, asdiscussed above.

As discussed above, the assembly 11 provides improved economy inconstruction. By performing the final step of forming the thin connectorwall 14 as an axial machining step, this step can be formed by simplereamer, boring tool, or step drill without substantial likelihood ofbreaking of the connector. Other configurations of the end wall 25 andgroove walls 27 and 28 may be employed within the scope of the inventionalthough it has been found that the disclosed construction providesexcellent functioning in the use of the coupling.

In making up the coupling, the user merely inserts the tube T throughthe one-piece sleeve and nut assembly 11 into endwise engagement withthe female coupling element. The assembly 1 1 is then slid along thetube to bring the threaded nut-portion 19 into threaded engagement withthe female coupling element threaded portion 18. The assembly 11 maythen be finger-tip advanced to bring the sleeve nose 20 into engagementwith the camming surface 17. Further, forcible torqueing of the nut maybe effected to deflect the sleeve nose 20 into engagement with the tubeT and concurrently effect a shearing of the connector wall 14 from thenut. The wall 14 projecting outwardly from the sleeve is caused to turnunder, as shown in FIG. 4, to have the distal end portion 29 extend intothe recess 24 and, thus, away from the nut portion 13 thus effectivelyavoiding projection of the broken connector to between the nut and tubeas may sometimes occur in the prior art couplings of this type.

Resultingly, when it is desired to disassemble the coupling, the userneed merely unthread the nut 13 from the female connector element 15,permitting the nut to be backed away from the sleeve 12 which is nowpermanently secured to the tube T, as shown in FIG. 5. The coupling maybe connected and disconnected repeatedly as desired with the sleeveproviding the desired sealed connection between the tube and the femaleelement, as shown in FIG. 4.

As shown in FIG. 4, the frangible connector 14 tends to shear adjacentnut end wall 25, thus effectively eliminating a projection on nut 13which might tend to bind with the projection of the broken connectorfrom the sleeve. The wall 25, thus, acts as a camming surface acting toeffect the desired under-turning of the connector portion as shown inFIG. 4.

Thus, the coupling provides an improved low cost tube coupling which issimple and economical of construction while yet providing an improvedtube joint which may be readily disconnected when desired.

The foregoing disclosure of specific embodiments is illustrative of thebroad inventive concepts comprebended by the invention.

We claim:

1. For use with a female coupling element having a port defining anaxially inner camming surface and an axially outer thread, a one-piecemale coupling element for coupling a tube to said female couplingelement comprising i a tubular member having an axial bore adapted tocoaxially receive the tube to be coupled, an axially inner sleeveportion having a tapered outer surface adapted to engage said cammingsurface of the female coupling element and be deflected radiallyinwardly thereby into sealed, locked association with the tube as theresult of an axially inward movement of said inner portion thereagainst,an axially threaded nut outer portion adapted to threadedly engage saidthread of the female cou pling element for effecting axial movement ofsaid male coupling element relative to said female coupling element asan incident of rotation of the male mcouplingelement relative to thefemale coupling element, a frangible mid-portion connecting said sleeveportion and nut portion adapted to be broken adjacent said nut portionin the make-up of the coupling, said mid-portion being defined by aradially outwardly opening annular groove, and an annular recessextending coaxially about said bore from the axially inner end thereofto radially inwardly adjacent said mid-portion groove, said frangibleportion defining a radially thin connection extending axially betweensaid sleeve portion and nut portion and radially between said radiallyoutwardly opening annular groove and said annular recess and having aninner diameter substantially greater than the inner diameter of said nutportion whereby the broken frangible portion is caused to turn underfrom said sleeve portion substantially 180 and extend into said recessradially within the sleeve portion the end of said frangible portionfacing toward the axially inner end of the bore, whereby said frangibleportion is prevented from projecting to between the tube and said nutportion in the made-up arrangement of the coupling. 2. The couplingelement structure of claim I wherein said recess is defined by a radial,planar axially outer end surface.

3. The coupling element structure of claim 1 wherein said groove isdefined by a right cylindrical, radially inner bottom surface. I

4. The coupling element structure of claim 1 wherein said groove isdefined by radial, planar axially inner and outer side surfaces.

5. The coupling element structure of claim 1 wherein said recess isdefined by an axially outer end surface disposed substantiallycongruently to the axially outer end of said groove.

6. The coupling element structure of claim 1 wherein said frangibleportion has a radial thickness of approximately 0.003 inch where saidbore of said nut portion has a diameter approximately one-fourth inch orsmaller.

7. The coupling element structure of claim 1 wherein the depth of theannular recess and the strength characteristics of the frangiblemid-portion are preselected to correlate with the deflectibility of thesleeve axially inner portion whereby the sleeve inner portion isdeflected substantially into engagement with the tube prior to thebreaking of the frangible mid-portion in the make-up of the coupling.

8. The coupling element structure of claim 1 wherein said frangiblemid-portion is broken substantially at the nut portion.

9. The coupling element structure of claim 1 wherein said recess has aradial depth of a approximately 0.002 to 0.003 inch.

10. The coupling element structure of claim 1 wherein the radialthickness of said frangible portion is similar to the radial depth ofsaid recess.

11. A one-piece nut and sleeve tube-coupling element comprising:

an annular sleeve having a tapered, deflectible nose and an outer rigidend;

a nut having a rigid inner end and a bore adapted to coaxially snuglyreceive a tube to be coupled, the internal diameter of said sleeve beingsubstantially greater than said tube to define an annular recesstherebetween; and

a frangible, thin walled annular connector extending between said sleeveand nut coaxially of said bore, said frangible connector defining aradially thin connection extending axially between said sleeve and nutand having an inner diameter substantially greater than the innerdiameter of said nut whereby the broken frangible connector is caused toturn under from said sleeve substantially and extend into said recessradially within the sleeve, the end of said frangible connector facingtoward the axially inner end of the bore, whereby said frangibleconnector is prevented from projecting to between the tube and said nutin the made-up arrangement of the coupling.

12. The tube-coupling element of claim 11 wherein said sleeve has aninner diameter approximately 0.002 to 0.003 inch greater than the innerdiameter of the nut. i

13. The tube-coupling element of claim 11 wherein said connector has aconstant wall thickness.

' i III II i I. l

1. For use with a female coupling element having a port defining anaxially inner camming surface and an axially outer thread, a one-piecemale coupling element for coupling a tube to said female couplingelement comprising a tubular member having an axial bore adapted tocoaxially receive the tube to be coupled, an axially inner sleeveportion having a tapered outer surface adapted to engage said cammingsurface of the female coupling element and be deflected radiallyinwardly thereby into sealed, locked association with the tube as thEresult of an axially inward movement of said inner portion thereagainst,an axially threaded nut outer portion adapted to threadedly engage saidthread of the female coupling element for effecting axial movement ofsaid male coupling element relative to said female coupling element asan incident of rotation of the male coupling element relative to thefemale coupling element, a frangible mid-portion connecting said sleeveportion and nut portion adapted to be broken adjacent said nut portionin the make-up of the coupling, said mid-portion being defined by aradially outwardly opening annular groove, and an annular recessextending coaxially about said bore from the axially inner end thereofto radially inwardly adjacent said mid-portion groove, said frangibleportion defining a radially thin connection extending axially betweensaid sleeve portion and nut portion and radially between said radiallyoutwardly opening annular groove and said annular recess and having aninner diameter substantially greater than the inner diameter of said nutportion whereby the broken frangible portion is caused to turn underfrom said sleeve portion substantially 180* and extend into said recessradially within the sleeve portion the end of said frangible portionfacing toward the axially inner end of the bore, whereby said frangibleportion is prevented from projecting to between the tube and said nutportion in the made-up arrangement of the coupling.
 2. The couplingelement structure of claim 1 wherein said recess is defined by a radial,planar axially outer end surface.
 3. The coupling element structure ofclaim 1 wherein said groove is defined by a right cylindrical, radiallyinner bottom surface.
 4. The coupling element structure of claim 1wherein said groove is defined by radial, planar axially inner and outerside surfaces.
 5. The coupling element structure of claim 1 wherein saidrecess is defined by an axially outer end surface disposed substantiallycongruently to the axially outer end of said groove.
 6. The couplingelement structure of claim 1 wherein said frangible portion has a radialthickness of approximately 0.003 inch where said bore of said nutportion has a diameter approximately one-fourth inch or smaller.
 7. Thecoupling element structure of claim 1 wherein the depth of the annularrecess and the strength characteristics of the frangible mid-portion arepreselected to correlate with the deflectibility of the sleeve axiallyinner portion whereby the sleeve inner portion is deflectedsubstantially into engagement with the tube prior to the breaking of thefrangible mid-portion in the make-up of the coupling.
 8. The couplingelement structure of claim 1 wherein said frangible mid-portion isbroken substantially at the nut portion.
 9. The coupling elementstructure of claim 1 wherein said recess has a radial depth ofapproximately 0.002 to 0.003 inch.
 10. The coupling element structure ofclaim 1 wherein the radial thickness of said frangible portion issimilar to the radial depth of said recess.
 11. A one-piece nut andsleeve tube-coupling element comprising: an annular sleeve having atapered, deflectible nose and an outer rigid end; a nut having a rigidinner end and a bore adapted to coaxially snugly receive a tube to becoupled, the internal diameter of said sleeve being substantiallygreater than said tube to define an annular recess therebetween; and afrangible, thin walled annular connector extending between said sleeveand nut coaxially of said bore, said frangible connector defining aradially thin connection extending axially between said sleeve and nutand having an inner diameter substantially greater than the innerdiameter of said nut whereby the broken frangible connector is caused toturn under from said sleeve substantially 180* and extend into saidrecess radially within the sleeve, the end of said frangible connectorfacing toward the axially inner enD of the bore, whereby said frangibleconnector is prevented from projecting to between the tube and said nutin the made-up arrangement of the coupling.
 12. The tube-couplingelement of claim 11 wherein said sleeve has an inner diameterapproximately 0.002 to 0.003 inch greater than the inner diameter of thenut.
 13. The tube-coupling element of claim 11 wherein said connectorhas a constant wall thickness.